Drill



W. K. SCHAEFER, H. G. GREER AND E. S. McCULLOUGH.

BILL.

APPLICATION FILED MAY 14. 1921.

Patented Jan. 17;1922.-

56/7 6121 W ISc/m e/ b. GT-Grer.

UNITED STATES P ATENT OFFICE.

WILLIAM K. SGHAEFER, HENRY G. GREER, AIND ELZADOBE S. MCCULLOUGH, 0F

' FAIRMQNT, WEST VIRGINIA.

DRILL.

To all whom. it may concern:

Be it known that we, \VILLIA'M K. SCHAEFER, HENRY G. GREEK, and ELZADORE S. MoCnLLoUGH, citizens of the United States, residing at Fairmont, in the county of Marion and State of lVest Virginia, have invented certain new and useful Improvements in Drills, of which the following is a specification, reference being had to the accompanying drawings.

This invention relates to certain improvements in drills and has relation more particularly to a device of this general character especially designed and adapted for use in connection with coal mining, and it is an object of the inventionrto provide a novel and improved device of'this general character embodying a plurality of bits, together with means whereby said bits may be effectively maintained in assembled relation during a working operation.

The invention consists in the details of construction and in the combination and arrangement of the several parts of our improved drill whereby certain important advantages are attained and the device rendered simpler, less expensive and otherwise more convenient and advantageous for use, as will be hereinafter more fully set forth.

The novel features of our invention will hereinafter be definitely claimed.

In order that our invention may be the betterunderstood, we will nowproceed to describe the same with reference to the accompanying drawings, wherein:

Figure 1 is a fragmentary view in elevation illustrating a drill constructed in accordance with an embodiment of our invention; and

Figure 2 is a view partly in section and partly in elevation of the device as herein I set forth.

Specification of Letters Patent. I Patented J an. 17,- 1922.

Application filed May 14, 1921.

Serial No. 469,701.

4 denotes a central cutting bit having one. end portion continued by a shank 5 which is directed through the bore of the sleeve 3, said shank being of a length in excess of the length of the sleeve so that the outer or free end portion of said shank will extend beyond the outer or free end of the sleeve 3.

The side walls or faces of the central cutting bit 4 adjacent the shank 5 are disposed in convergence toward the working or cutting end of the bit 4 whereby the inner portion of the bit 4, or that portion immediately adjacent the shank 5, constitutes a wedge 6. The working end portion of the central cutting bit 4 is formed with a pair of reversely extending cutting teeth 7. T

Fitting within the socket 2 of the head H at opposite sides of the central cutting bit 4 are the side bits 8. The portions of the side bits 8 extending within the socket 2 have the side faces opposed to the central cuttingbit 4 inclined or beveled complemental to the converging side faces of the wedge portion 6 of the central cutting bit 4. By this arrangement, as the central cutting bit 4 is forced outwardly, the wedge portion 6 thereof coacts with the beveled faces of the side cutting bits 8 to effectually clamp said bits 8 in working or applied position.

The outer or working end portions of the side bits 8 are curved outwardly, as at 9, to space the same from the adjacent portion ofthe central cutting bit 4.

-:I n practice, the shank 5 of the central cutting bit 4 is first inserted through the bore of the sleeve. 3 through the head end of said sleeve and after which the side bits 8 are then applied. The sleeve 3 is then screwed or otherwise inserted within the socket 1 of thestock S and when the outer end of.the shank 5 comes into contact with the base of the socket 1 and the sleeve 3 is continued inwardly of said socket, said shank 5 and the central bit 4 will be moved outwardly resulting in'the requisite coaction between the wedge portion 6 and the complemental inclined or beveled portions of the side bits 8. By this means, it will be readily understood that the bits 4 and 8 may be applied or removed with con venience and facility.

The head H is provided at its opposite sides with the outstanding ribs or flanges 10 which, when the head H is in applied position, are substantially in continuity with the blade of the spiral or anger.

From the foregoing description it is thought to be obvious that a drill constructed in accordance with our invention is particularly well adapted for use by reason of the convenience and facility with which it may be assembled and operated, and it will also be obvious that our invention is susceptible of some change and modification without departing from the principles and WLLQ JhQbit adjimentfltheshank-having its'side walls converging toward the working end of the bit, said shank being of a length to extend beyond the outer end of the tubular extension and being freely movable therein, and side bits seating within the head, the walls of the side bits opposed to the con verging walls of the central bit being correspondingly beveled, the converging walls of t e central bit and the converging faces of the side bits contacting to clamp the side bits in applied position.

2. In combination with a drill stock provided with a socket in an end portion thereof, a hollow head having a tubular extension seating within the socket of the stock, a bit arranged centrally within said head and having a shank extending through said tubular extension, the portion of the bit adjacent the shank having its side walls converging toward the working end' of the bit, said shank being of a length to extend beyond the outer end of the tubular extension and being freely movable therein, and side bits seating within the head, the Walls of the side bits opposed to the converging Walls of the central bit being correspondingly beveled, the converging walls of the central bit and the converging faces of the side bits contacting to clamp the sidebits in applied position.

3. In combination with a drill stock provided with a socket in an end portion thereof, a hollow head having a tubular extension seating within the socket of the stock, a bit arranged centrally within, said head and having a shank extending through said tubular extension, the portion of the bit adjacent the shank having its side walls converging toward the working end of the bit, said shank being of a length to extend beyond the outer end of the tubular extension and being freely movable therein, the inner end of the shank contacting with the base of the socket and side bits seating within the head, the walls of the side bits opposed to the converging walls of the central bit being correspondingly beveled. the tubular extension of the head threading within the socket of the stock, movement of the extension of the head inwardly of the socket causing the central bit to clamp the side bits in applied position. 7

In testimony whereof we hereunto afiix our signatures.

W'ILLIAM K. SCHAEFER. HENRY G. GREER. ELZADORE S. MGCULLOUGH. 

